"From our perspective it's disappointing, and not just from a parochial perspective either - in my view this is actually bad for the lamb category, because the way things are structured currently we have New Zealand lamb basically going up to the UK in their off season when they don't produce product.

"For them to supply for 12 months of the year [means] you'll have a lot of old season lamb at their end to maintain that, and I don't think that's a great experience for the consumers."

Marks & Spencer only imported small volumes from New Zealand, he said.

"About 29,000 lambs is the figure I've been told.

"To put it in context, we're talking about 10 or 12 New Zealand farms and of that, only about half of the carcass - they don't use the whole carcass at Marks & Spencer stores."

Other supermarkets could pick up the market share and business if consumers were not getting what they wanted from Marks & Spencer, Mr Parsons said.